Timing control circuit shared by a plurality of banks

ABSTRACT

Apparatuses and methods for providing activation timings of sense amplifiers in a semiconductor device are described. An example apparatus includes: a first memory bank including at least one first sense amplifier that is enabled responsive to a first activation signal; a second memory bank including at least one second sense amplifier that is enabled responsive to a second activation signal; and a control circuit that receives a control signal. The control circuit includes a delay circuit that provides a delayed control signal by delaying the control signal, a first sense amplifier control circuit coupled to the first delay circuit and provides the first activation signal respective to the delayed control signal when the first memory bank is designated, and a second sense amplifier control circuit coupled to the delay circuit and provides the second activation signal respective to the delayed control signal when the second memory bank is designated.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.15/682,775 filed Aug. 22, 2017, issued as U.S. Pat. No. 10,229,730 onMar. 12, 2019, which is a continuation of U.S. patent application Ser.No. 15/245,727 filed Aug. 24, 2016, issued as U.S. Pat. No. 9,779,800 onOct. 3, 2017, which claims priority to U.S. Provisional Application No.62/219,560, filed Sep. 16, 2015. The aforementioned applications andpatents are incorporated herein by reference, in their entirety, for anypurpose.

BACKGROUND

In the semiconductor memory industry, there is a technical trend ofadopting newer architecture with a larger number of memory banks inorder to achieve higher access speed. For example, among synchronousdynamic random-access memories (SDRAM), double data rate two (DDR2)SDRAM may include four memory banks, DDR type three (DDR3) SDRAM mayinclude eight memory banks, DDR fourth generation (DDR4) SDRAM mayinclude sixteen memory banks, and DDR4e may include thirty-two memorybanks. Development of processes for fine patterns of semiconductordevices so called 1X-nm technology generation or later has been animportant theme in order to keep a small size of the semiconductordevices while having a larger number of memory banks. In the 1X-nmtechnology processes, increasing costs of the processes have been acritical issue. It is, therefore, important to develop devices in acost-competitive manner by utilizing existing process technologies. Onesolution to avoid such cost increase may be reducing areas of peripheralcircuits while increasing areas for memory cells.

In recent years, there has been an effort to reduce the areas of theperipheral circuits. For example, Japanese patent applicationpublication H11-203867 (JPA H11-203867) describes a row access controlcircuit to secure a restore level of memory cell by preventing aselected memory cell from being precharged before a lapse of a minimumrow active period (tRAS). In particular, the row access control circuitdescribed in JPA H11-203867 includes a single delay circuit which delaysan active command to provide a precharge control signal which is used tokeep a row access strobe (RAS) signal at an active level. JPA H11-203867also describes that the single delay circuit is shared by a plurality ofmemory banks and the precharge control signal is provided selectively toone of the plurality memory banks to control a precharge operationtiming for the one of the plurality memory banks. Thus, the prechargetimings for the plurality of memory banks can be individuallycontrolled.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram of a semiconductor device inaccordance with the present disclosure.

FIG. 2A is a schematic block diagram of a row control circuit accordingto an embodiment of the present disclosure.

FIG. 2B is a schematic block diagram of a row control circuit accordingto an embodiment of the present disclosure.

FIG. 2C is a schematic block diagram of the pulse width extensioncircuit in the row control circuit of FIG. 2B according to an embodimentof the present disclosure.

FIG. 3 is a timing diagram of signals corresponding to operations of therow control circuit according to FIG. 2A, according to an embodiment ofthe present disclosure.

FIG. 4 is a schematic block diagram of a bank address register block inthe row control circuit, according to an embodiment of the presentdisclosure.

FIG. 5 is a timing diagram of signals corresponding to operations of theregister control circuit in the bank address register block of FIG. 4,according to an embodiment of the present disclosure.

FIG. 6 is a schematic block diagram of a row control circuit, accordingto embodiment of the present disclosure.

FIG. 7 is a circuit diagram of a sense amplifier according to anembodiment of the present disclosure.

FIG. 8 is a timing diagram of signals corresponding to operations of therow control circuit of FIG. 6, according to an embodiment of the presentdisclosure.

FIG. 9 is a schematic block diagram of a row control circuit, accordingto an embodiment of the present disclosure.

FIG. 10 is a timing diagram of signals corresponding to operations ofthe row control circuit of FIG. 9, according to an embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Among peripheral circuits of a semiconductor device, row access strobe(RAS) timing control circuits occupy a significantly large area in thesemiconductor device. An increase in the number of memory banks resultsin an increase in the area used for the RAS timing control circuitsbecause one RAS timing circuit is provided for each memory bank of theplurality memory banks of the semiconductor device. For example, DDR2SDRAM may include four RAS timing control circuits, DDR3 SDRAM mayinclude eight RAS timing control circuits, DDR4 SDRAM may includesixteen RAS timing control circuits, and DDR4e may include thirty-twoRAS timing control circuits.

As will be described in more detail below, a semiconductor deviceaccording to the present disclosure includes a row timing controlcircuit which may be configured to control timings of a plurality ofsense amplifiers in a corresponding plurality of memory banksrespectively.

Various embodiments of the present invention will be explained below indetail with reference to the accompanying drawings. The followingdetailed description refers to the accompanying drawings that show, byway of illustration, specific aspects and embodiments in which thepresent invention may be practiced. These embodiments are described insufficient detail to enable those skilled in the art to practice thepresent invention. Other embodiments may be utilized, and structure,logical and electrical changes may be made without departing from thescope of the present invention. The various embodiments disclosed hereinare not necessary mutually exclusive, as some disclosed embodiments canbe combined with one or more other disclosed embodiments to form newembodiments.

FIG. 1 is a functional block diagram of a semiconductor device inaccordance with the present disclosure. The semiconductor device 10includes a memory cell array 11 that can store data. The memory cellarray 11 may be included in an array area. The memory cell array 11includes a plurality of memory banks 12, including a first bank (Bank0),a second bank (Bank1) . . . and Bank15. The number of the plurality ofmemory banks in this example is sixteen; however, it is not limited tosixteen. Each memory bank of the plurality of memory banks 12 has aplurality of word line drivers (WDs) 13 and a plurality of senseamplifiers (SM) 14 and DRAM memory cells (MCs) 15 accessed via bit linesBL and word lines WL driven by the plurality of WDs 13.

The semiconductor device 1 includes several circuits in a peripheralarea outside of the array area. An input/output (I/O) circuit 16 iscoupled to external devices. The I/O circuit 16 receives signals fromthe external devices and provides the signals including command signals(CMD), a set of bank address signals (BA) and address signals (ADD),clock signals (CLK), and data signals (DATA) to internal circuitsincluding a command decoder (CDEC) 17, an address buffer circuit (ADDB)18, a clock buffer circuit (CLKB) 19, and a data control circuit (DCTL)20, respectively. The I/O circuit 16 also receives data signals from theDCTL 20 and provides the data signals to the external devices.

The command decoder (CDEC) 17 receives the command signals (CMD) andgenerates corresponding control signals to read data from and write datato the memory cell array 11. The control signals include an activecommand signal MDBAT and a precharge command signal MDDAT provided to arow controller (RCTL) 21 and read/write (RD/WR) command signals providedto a column controller (CCTL) 22. The address buffer circuit (ADDB) 18receives the bank address signals (BA) and the address signals (ADD) andprovides row bank address information (RBA<3:0>) and row addressinformation (RADD) to the RCTL 21, and further provides column addressinformation (CADD) to the CCTL 22. The clock buffer circuit (CLKB)receives the CLK signals and provides internal clock signals ICLK. TheDCTL 20 is a “read and write” circuitry which provides data to bewritten from the I/O circuit 16 to the memory cell array 11, andprovides data to be read out from the memory cell array 11 to the I/Ocircuit 16. The CCTL 22 is a column control circuit which providescolumn access signals (CAC) based on the read/write (RD/WR) commandsignals from the CDEC 17 and the CADD from the ADDB 18. The RCTL 21receives the active command signal MDBAT and the recharge command signalMDDAT from the CDEC 17, and the row bank address information (RBA<3:0>)and the row address information (RAM)) from the ADDB 18. Based on thesereceived signals, the RCTL 21 provides bank activation signals(MCBAT<15:0>), sense amplifier (SA) activation signals (MCSAE <15:0>)and row access signals (RAC) to the memory cell array 11. In thisexample, the RCTL includes a row control circuit 210 illustrated in FIG.2A.

FIG. 2A is a schematic block diagram of the row control circuit 210according to an embodiment of the present disclosure. A first bankaddress information decoder (DEC1) 211 decodes the row bank addressinformation RBA<3:0> which is four-bit information and provides WL bankselect signals WBS<15:0>. Bank active control circuits BCTL<15:0> 212may be flip-flop circuits where each flip-flop circuit is associatedwith a respective one of the memory banks 12 in FIG. 1, and where eachflip-flop circuit includes a set node, a reset node and an enable node.The WBSs are provided to respective enable (E) nodes of the BCTLs<15:0>212. A reset node of each BCTL 212 is also coupled to its respectiveinactivation signal MDDAT′. On the other hand, the active command signalMDBAT is provided in common to the set (S) nodes of the BCTLs<15:0> 212.The BCTLs<15:0> 212 may provide respective bank activation signalsMCBAT<15:0> as active when the active command signal MDBAT and therespective WL bank select signal WBS<15:0> are indicative of beingactive. Activation of each WL bank select signal indicates designationof a respective memory bank. On the other hand, each bank active controlcircuit BCTL 212 may provide the respective bank activation signal MCBATas inactive upon receipt of the respective inactivation signal MDDAT′without receiving the respective WBS at the enable node of each BCTL212. Each of the bank activation signals MCBAT<15:0> may be used todefine a bank activation period of a respective memory bank. In otherwords, each of the bank activation signals MCBAT<15:0> may be used todefine a timing of controlling activation and deactivation of selectedone or ones of word lines in a respective memory bank.

A WL-SA delay circuit 213 may delay the active command signal MDBAT andprovide a first delayed active command signal MDSAT. In one embodiment,a delay of the WL-SA delay circuit 213 may be based on a period of timewhen a pair of bit lines is prepared to be sensed. In other words, thedelay of the WL-SA delay circuit 213 is based on a period of time forvoltages of a pair of bit lines to be separated enough responsive to adata stored in a memory cell after a word line is activated. The firstdelayed active command signal MDSAT is provided in common to senseamplifier control circuits SCTL<15:0> 214 as well as to a bank address(BA) register block 215 which is a first bank address control circuit.

The sense amplifier control circuits SCTL<15:0> 214 may be flip-flopcircuits where each flip-flop circuit is associated with a respectiveone of the memory banks 12 in FIG. 1, where each flip-flop circuitincludes a set node, a reset node and an enable node. Each senseamplifier control circuit SCTL 214 is substantially equal in internaloperation to the bank active control circuit BCTL 212 except for inputand output signals. For example, the first delayed active command signalMDSAT is provided in common to set nodes of the sense amplifier controlcircuits SCTL<15:0> 214. On the other hand, a reset node of each senseamplifier control circuit SCTL 214 may receive the respectiveinactivation signal MDDAT′. An enable node of each sense amplifiercontrol circuit SCTL 214 may receive a respective SA bank select signalSBS from the BA register block 215. Each sense amplifier control circuitSCTL 214 may provide a respective SA activation signal MCSAE as activewhen the first delayed active command signal MDSAT and the respective SAbank select signal SBS are indicative of being active. Activation ofeach SBS indicates designation of a respective memory bank. On the otherhand, each sense amplifier control circuit SCTL 214 may provide therespective SA activation signal MCSAE as inactive responsive to anassertion of the respective inactivation signal MDDAT′ without receivingSBS at the enable node of each SCTL 214. The sense amplifiers in eachmemory bank are enabled once the sense amplifiers receive the respectiveSA activation signal MCSAE being active. The sense amplifiers in eachmemory bank are disabled once the sense amplifiers receive therespective SA activation signal MCSAE being deactivated. Thus, each SAactivation signal MCSAE may be used to activate or deactivate senseamplifiers of its respective memory bank.

The BA register block 215 may include a bank address register module 216and a second bank address information decoder (DEC2) 217. The bankaddress register module 216 receives the row bank address informationRCA<3:0>, the active command signal MDBAT and the first delayed activecommand signal MDSAT and provides row sense-amp bank address informationRSBA<3:0>. The bank address register module 216 will be described indetails referring to FIGS. 4 and 5. The second bank address informationdecoder (DEC2) 217 decodes the RSBA<3:0> and provides SA bank selectsignals SBS<15:0>.

Each of the logic gates LG<15:0> 218 includes an AND gate which receivesa respective WBS at one input node and a precharge command signal MDDATprovided to the other input node. Each logic gate of the logic gatesLG<15:0> 218 may provide the respective inactivation signalsMDDAT′<15:0> when the precharge command signal MDDAT and the respectiveWBSs<15:0> are both indicative of being active.

FIG. 2B is a schematic block diagram of the row control circuit 210according to an embodiment of the present disclosure. The row controlcircuit 210 is similar to the row control circuit 210 of FIG. 2A.Description of components in FIG. 2B corresponding to componentsincluded in FIG. 2A and previously described will not be repeated.However, in contrast to the row control circuit 210 of FIG. 2A, the rowcontrol circuit 210 of FIG. 2B may include a pulse width extensioncircuit PWE 220 that provides an extended active command signal EMDBAThaving an extended pulse width responsive to the active command signalMDBAT. Instead of the active command signal MDBAT, the extended activecommand signal EMDBAT may be provided to the set (S) nodes of theBCTLs<15:0> 212, the WL-SA delay circuit 213 and the bank addressregister module.

FIG. 2C is a schematic block diagram of the pulse width extensioncircuit PWE 220 in the row control circuit 210 of FIG. 2B according toan embodiment of the present disclosure. The pulse width extensioncircuit PWE 220 may receive the active command signal MDBAT. An inverter221 may invert the active command signal MDBAT and may further providean inverted active command signal MDBATB. The pulse width extensioncircuit PWE 220 may further include a signal extension delay circuit SED222 that may provide a delayed MDBATB signal that has a delay relativeto the MDBATB signal, where the delay is corresponding to a pulse widthextension. The pulse width extension circuit PWE 220 may farther includean SR latch 223 that may receive the MDBATB signal at a set (S) inputand the delayed MDBATB signal at a reset (R) input and may furtherprovide an extended active command signal EMDBAT. The EMDBAT signal mayhave a longer pulse width, such as a half of a minimum interval betweenapplying an active command signal to one memory bank and applying nextactive command for another memory bank (tRRDmin). In comparison, theMDBAT signal may have a pulse width of approximately a half of a minimumclock cycle (tCKmin). Even if a clock cycle CK may become short, the rowcontrol circuit 210 may generate stable signals (e.g., MDSAT signal)responsive to the MDBAT signal using the EMDBAT signal having theextended pulse width.

FIG. 3 is a timing diagram of signals corresponding to operations of therow control circuit according to FIG. 2A, according to an embodiment ofthe present disclosure. For example, the signals in the timing diagramin FIG. 3 are active-high signals. The active command signal MDBAT hasshort command pulses. In FIG. 3, multiple active commands are seriallyissued with the minimum time interval tRRDmin. However, the interval ofthe active commands being issued is not limited to the tRRDmin.

In this timing diagram, MCBAT<0>, the first bank activation signal forBank0 is activated in response to the first activation of MDBAT andprovided from the BCTL<0>, MCBAT<1>, the second bank activation signalfor Bank1, is activated in response to the second activation of MDBATand provided from the BCTL<1>. MCBAT<2>, the third bank activationsignal for Bank2, is activated in response to the third activation ofMDBAT and provided from the BCTL<2>. The other banks follow bankactivation operations in a similar manner. On the other hand, once aprecharge command signal MDDAT also having short command pulses becomesactive, MCBAT<0> becomes inactive in response to receipt of a firstinactivation signal MDDAT′<0> for Bank0 at the BCTL<0>. The other banksfollow bank deactivation operations in a similar manner.

In this embodiment, because of having the BA register block, the rowcontrol circuit can provide a WL-SA delay to the plurality of senseamplifier activation signals MCSAEs for the plurality of memory banks byusing a single delay circuit, that is the WL-SA delay circuit. The firstdelayed active command signal MDSAT has short command pulses where theMDSAT is provided by delaying the MDBAT by the WL-SA delay circuit. Inthis timing diagram, MCSAE<0>, the first SA activation signal for senseamplifiers of Bank0, is activated in response to the first activation ofMDSAT and provided from the SCTL<0>, MCSAE<1>, the second SA activationsignal for sense amplifiers of Bank1, is also activated in response tothe second activation of MDSAT and provided from the SCTL<1>. MCSAE<1>,the third SA activation signal for Bank2, is activated in response tothe third activation of MDSAT and provided from the SCTL<1>. Senseamplifiers of the other banks follow SA activation operations in asimilar manner. Thus, it is possible to provide delays to activationtimings of sense amplifiers of each bank respectively from one WL-SAdelay circuit.

FIG. 4 is a schematic block diagram of a bank address register block 400corresponding to the BA register module 216 in the row control circuit210, according to one embodiment of the present disclosure. The bankaddress register block 400 may include a register control circuit 401and a bank address register circuit 402.

The register control circuit 401 includes an input timing controlcircuit (IPTC) 403 and an output timing control circuit (OPTC) 404. TheIPTC 403 may selectively activate one of input control signals SELI<3:0>responsive to the active command signal MDBAT. For example, the IPTC 403may select one of the input control signals for activation responsive toeach assertion of the active command MDBAT. In one embodiment, the IPTC403 may activate the input control signals in an order of SELI<0>,SELI<1>, SELI<2>, and SELI<3>. The OPTC 404 may substantially be thesame as the IPTC 403 except that an input node of the OPTC 404 receivesthe first delayed active command signal MDSAT and that output nodes ofthe OPTC 404 provide output control signals SELO<3:0>. As a result, eachoutput control signal SELO may be activated after a predetermined periodfrom activation of a corresponding input control signal SELI. In oneembodiment, the predetermined period may be substantially equal to adelay of the WL-SA delay circuit.

The bank address register circuit 402 may include a plurality ofregister units (RUs). For example, the plurality of RUs may be a firstregister unit (RU0) 405, a second register unit (RU1) 406, a thirdregister unit (RU2) 407, and a fourth register unit (RU3) 408. Each RUcorresponds to a respective bit of bank address information, includingrow bank address information (RBA) and row sense-amp bank addressinformation (RSBA). The number of the RUs is not limited to four asshown in FIG. 4 but may depend on the number of bits of the bank addressinformation. Each RU may include a plurality of latch circuits whichfunction as bank address registers. Each latch circuit ma latch an inputsignal, which is one bit of the row bank address information, responsiveto assertion of the respective input control signal SELI. Each latchcircuit may output the latched signal as one bit of the row sense-ampbank address information, responsive to assertion of the respectiveoutput control signal SELO. As a result, the bank register circuit 402can apply a predetermined time of delay, which may be the same as adelay of the WL-SA delay circuit, to the bank address information. Thenumber of latch circuits contained in each register unit RU is notlimited to four as shown in FIG. 4. It is also independent of the numberof the RUs. The number of latch circuits may be based on a relationbetween tRRDmin and the delay of the WL-SA delay circuit. For example,as the delay of the WL-SA delay circuit is longer than the tRRDmin, morelatch circuits may be included.

FIG. 5 is a timing diagram of signals corresponding to operations of theregister control circuit 401 of FIG. 4, according to an embodiment ofthe present disclosure. For example, the signals in the timing diagramin FIG. 5 are active-high signals. The active command signal MDBAT hasshort command pulses. In this timing diagram, the IPTC may activateSELI<0>, the first input control signal, in response to the firstactivation of MDBAT and provide the activated SELI<0>. The IPTC may alsoactivate SELI<1>, the second input control signal, in response to thesecond activation of MDBAT and provide the activated SELI<1>. The IPTCmay also activate SELI<2>, the third input control signal, in responseto the third activation of MDBAT and provide the activated SELI<2>. Theother SELIs will follow activation operations in a similar manner. Thefirst delayed active command signal MDSAT also has short command pulses.The OPTC activates SELO<0>, the first output control signal, in responseto the first activation of MDSAT and provides the activated SELO<0>. Theother SELOs follow activations in a similar manner and become active. Inthis embodiment, the register control circuit 401 may reflect the delaysbetween activation of word lines and activation of sense amplifiers,that is the WL-SA delay, on RSBAs further processed into SA bank select(SBS) signals by using the active command signal MDBAT and the firstdelayed active command signal MDSAT. Thus the WL-SA delay between theMDBAT and the first delayed active command signal MDSAT can be providedto sense amplifiers on each bank.

FIG. 6 is a schematic block diagram of a row control circuit 600,according to another embodiment of the present disclosure. The BAregister block2 is substantially the same as the BA register block1except for its inputs and outputs. A first bank address informationdecoder (DEC1) 611, Bank active control circuits BCTL<15:0> 612, a WL-SAdelay circuit 613, sense amplifier control circuits SCTL<15:0> 614, afirst bank address (BA) register block 615, a first bank addressregister module 616, a second bank address information decoder (DEC2)617 and logic gates LG<15:0> 618 function similarly to the correspondingcircuits previously described with reference to FIG. 4. Furthermore, thefirst delayed active command signal MDSAT may also be provided to senseamplifier overdrive control circuits OCTL<15:0> 620. The sense amplifieroverdrive control circuits OCTL<15:0> 620 includes 16 OCTLs including afirst OCTL<0>, a second OCTL<1>, etc.

In this embodiment, another delay circuit, a sense amplifier (SA)overdrive delay circuit 61 defines an overdrive operation period forsense amplifiers that is shared by the memory banks in a similar mannerthat the WL-SA delay is added. For example, the SA overdrive delaycircuit 619 may receive the first delayed active command signal MDSATfrom the WL-SA delay circuit 613 and provide a second delayed activecommand signal MDSAP. In one embodiment, a delay of the SA overdrivedelay circuit 619 may be based on a period of time for a singleoverdrive operation for a sense amplifier. The second delayed activecommand signal MDSAP is provided to the sense amplifier overdrivecontrol circuit OCTL<15:0> 620 as well as to a bank address (BA)register block2 623 which is a second bank address control circuit.

Each sense amplifier overdrive control circuit OCTL 620 controls anoverdrive operation for sense amplifiers of a corresponding bank. Eachsense amplifier overdrive control circuit OCTL 620 includes firstoverdrive control circuit units OCTLU1<15:0> 621 and second overdrivecontrol circuit units OCTLU2<15:0> 622. The OCTLU1 621 and the OCTLU2622 may be flip-flop circuits provided respectively to the memory banks12 in FIG. 1, where each flip-flop circuit includes a set node, a resetnode and an enable node. Thus OCTLU1 621 and OCTLU2 622 aresubstantially the same in internal operation to the BCTL1 612 and theSCTL1 614. The first delayed active command MDSAT is provided in commonto set nodes of the first overdrive control circuit units OCTLU1<15:0>621. Each first overdrive control circuit unit OCTLU1 621 may activate acorresponding SA overdrive control signal MCSAPODB based on the firstdelayed active command MDSAT from the WL-SA delay circuit 613 responsiveto an assertion of a corresponding SA bank select signal SBS from thefirst bank address (BA) register block 615. The assertion of each SBSindicates designation of a respective memory bank. Each first overdrivecontrol circuit unit OCTLU1 621 may deactivate the corresponding SAoverdrive control signal MCSAPODB responsive to an assertion of acorresponding SA non-overdrive signal MCSAPB without receiving thecorresponding SA bank select signal SBS at the enable node from thefirst BA register block 615.

A second bank address register block 623 may include a second bankaddress register module 624 and a third bank address information decoder(DEC3) 625. The second bank address register module 624 receives the rowbank address information RBA<3:0>, the active command signal MDBAT andthe second delayed active command signal MDSAP, and provides rowoverdrive bank address information RPBA<3:0>, similarly to the firstbank address register module 616. The second bank address registermodule 624, however, uses the second delayed active command MDSAPinstead of the first delayed active command MDSAT. The third bankaddress information decoder (DEC3) 625 decodes the RPBA<3:0> andprovides overdrive (OD) bank select signals PBS<15:0>.

The second delayed active command MDSAP is also provided in common toset nodes of second overdrive control circuit units OCTLU2<15:0> 622.Each second overdrive control circuit unit OCTLU2 622 may activate acorresponding SA non-overdrive signal MCSAPB based on the second delayedactive command MDSAP responsive to an assertion of a correspondingoverdrive (OD) bank select signal PBS provided from the second bankaddress register block 623. The assertion of each PBS indicatesdesignation of a respective memory bank. Each second overdrive controlcircuit unit OCTLU2 622 may deactivate the corresponding SA overdrivecontrol signal MCSAPODB responsive to a corresponding inactivationsignal MDDAT′.

Overdrive operations of sense amplifiers are executed for acceleratingactivation of the sense amplifiers by using applying an overdrivevoltage (VOD) which is greater than a power voltage of a sense amplifier(VSAP). A circuitry relationship between the VOD and the VSAP isdepicted in FIG. 7. FIG. 7 is a circuit diagram of a sense amplifier 701corresponding with the row control circuit of FIG. 6. A source of afirst p-channel transistor 702 is coupled to the VOD and a gate of thefirst p-channel transistor 702 is coupled to the SA overdrive controlsignal MCSAPODB. A source of a second p-channel transistor 703 iscoupled to the VSAP and a gate of the second p-channel transistor 703 iscoupled to the SA non-overdrive signal MCSAPB. Drains of the firstp-channel transistor 702 and the second p-channel transistors arecommonly coupled to a power supply node of the sense amplifier 701. Thesense amplifier 701 is coupled to a pair of bitlines providing a pair ofcomplementary signals BL and BLB and senses a potential differencebetween the BL and BLB. A ground node of the sense amplifier 701 iscoupled to a drain of an n-channel transistor 704 which has a gate nodecoupled to a signal MCSAN and a source node coupled to a negative powervoltage VSAN. When the SA overdrive control signal MCSAPODB isactivated, the VOD is provided for accelerating activation of the senseamplifier 701. When SA non-overdrive signal MCSAPB is activated, theoverdrive control signal MCSAPODB is deactivated by the OCTLU1 as wellas and VSAP is provided for sensing operations of the sense amplifier701.

FIG. 8 is a timing diagram of signals corresponding to operations of therow control circuit 600 of FIG. 6, according to an embodiment of thepresent disclosure. As previously described, the first delayed activecommand signal MDSAT has short command pulses. In this timing diagram,MCSAE<0>, the first SA activation signal for sense amplifiers of Bank0,is activated in response to the first activation of MDSAT and providedfrom the SCTL<0>. At the same time, the SA overdrive control signalMCSAPODB<0>, that is an active-low signal, may be activated to executeoverdrive operations to accelerate the activation of the senseamplifier. The other sense amplifiers follow SA activation operations ina similar manner.

On the other hand, the second delayed active command signal MDSAP alsohaving short command pulses becomes active with a delay of the SAoverdrive delay circuit from the MDSAT. In this timing diagram,MCSAPB<0>, the first SA non-overdrive signal for sense amplifiers ofBank0, is activated in response to the first activation of MDSAP. The SAnon-overdrive signal MCSAPB<0> becomes at active-low level to stop theoverdrive operation for sense amplifiers of Bank0 in response to thefirst activation of MDSAP, by deactivating MCSAPODB<0>. The other senseamplifiers follow the overdrive deactivation operations in a similarmanner at the following active periods of MDSAP. Thus, it is possible toactivate an overdrive operation for sense amplifiers of each bank forperiod defined by the SA overdrive delay circuit.

FIG. 9 is a schematic block diagram of a row control circuit 900,according to another embodiment of the present disclosure. A first bankaddress information decoder (DEC1) 911, Bank active control circuitsBCTL<15:0> 912, a WL-SA delay circuit 913, sense amplifier controlcircuits SCTL<15:0> 914, the first bank address (BA) register block 915,a first bank address register module 916, a second bank addressinformation decoder (DEC2) 917 and first logic gates LG1<15:0> 918function similarly to the corresponding circuits as previously describedwith reference to FIG. 4. In this embodiment, a refresh delay circuit919 may define a period of a single refresh operation cycle and may beshared by the memory banks in a similar manner as the WL-SA delay isshared. For example, the refresh delay circuit 919 may use a refreshdelay in order to provide a third delayed active command MDROT as wellas the first delayed active command signal MDSAT is provided based onthe WL-SA delay. Thus, the refresh delay may be based on a period oftime for a single refresh operation.

A third bank address register block 923 is substantially the same as thefirst bank address register block 915 except for its inputs and outputs.The third bank address register block 923 may include a third bankaddress register module 924 and a fourth bank address informationdecoder (DEC4) 925. The third bank address register module 924 receivesthe row bank address information RBA<3:0>, the active command signalMDBAT and the third delayed active command signal MDROT and provides rowrefresh bank address information RABA<3:0>, similarly to the first bankaddress register module 916. The third bank address register module 924,however, uses the third delayed active command MDROT instead of thefirst delayed active command MDSAT. The fourth bank address informationdecoder (DEC4) 925 decodes the RRBA<3:0> and provides refresh (REF) bankselect signals FBS 15:0>.

The third delayed active command MDROT may also be provided in common toset nodes of a plurality of second logic gates LG2 920. Each secondlogic gate LG2 may propagate the third delayed active command MDROT as acorresponding internal refresh end signal MCROT responsive to anassertion of a respective REF bank select signal FBS from the third bankaddress register block 923. The assertion of each FBS indicatesdesignation of a respective memory bank. In a refresh operation, aplurality of third logic gates LG3<15:0> 921 receives a refresh statesignal MCRFT. During refresh operations when the refresh state signalMCRFT is active, each logic gate of the third logic gates LG3<15:0> 921may also receive corresponding internal refresh end signals MDROT<15:0>and provide inactivation signals MDDAT′<15:0>. During normal operations,such as a read operation or a write operation, when the refresh statesignal MCRFT is not active, each logic gate of the third logic gatesLG3<15:0> 921 may also provide the corresponding inactive signalsMDDAT′<15:0> responsive to respective precharge command signalsPMDDAT<15:0> received from each logic gate of the first logic gatesLG1<15:0>.

FIG. 10 is a timing diagram of signals corresponding to operations ofthe row control circuit 900 of FIG. 9, according to an embodiment of thepresent disclosure. As previously described, the first delayed activecommand signal MDSAT becomes active and MCSAE<0>, the first SAactivation signal for sense amplifiers of Bank0, is activated inresponse to the first activation of MDSAT and provided from the SCTL<0>.On the other hand, the third delayed active command signal MDROT alsohaving short command pulses becomes active with a delay of the refreshdelay circuit in addition to the delay from the WL-SA delay circuit. Inthis timing diagram, MCROT<0>, the first of third delayed active commandsignal also having a pulse signal for sense amplifiers of Bank0, isactivated in response to the first active period of MDROT, thereby thecorresponding bank activation signal MCBAT<0> and the corresponding SAactivation signal MCSAE<0> are deactivated. The other sense amplifiersfollow the refresh operations in a similar manner at the followingactive periods of MDROT. Thus, it is possible to activate a refreshoperation for sense amplifiers of each bank for period defined by therefresh delay circuit.

Although this invention has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the inventions extend beyond the specificallydisclosed embodiments to other alternative embodiments and/or uses ofthe inventions and obvious modifications and equivalents thereof. Inaddition, other modifications which are within the scope of thisinvention will be readily apparent to those of skill in the art based onthis disclosure. It is also contemplated that various combination orsub-combination of the specific features and aspects of the embodimentsmay be made and still fall within the scope of the inventions. It shouldbe understood that various features and aspects of disclosed embodimentscan be combined with or substituted for one another in order to formvarying mode of the disclosed invention. Thus, it is intended that thescope of at least some of the present invention herein disclosed shouldnot be limited by the particular disclosed embodiments described above.

What is claimed is:
 1. An apparatus comprising: a delay circuitconfigured to provide a delayed command signal responsive to a commandsignal; a sense amplifier control circuit configured to provide a senseamplifier activation signal responsive to the delayed command signal;and a register configured to provide a piece of address information tothe sense amplifier control circuit responsive to the command signal andthe delayed command signal, and also configured to receive bank addressinformation, wherein the register comprises: a flip-flop; a first switchconfigured to transfer the bank address information to the flip-flopresponsive to the command signal; and a second switch configured toprovide a data in the flip-flop as the piece of address information tothe sense amplifier control circuit responsive to the delayed commandsignal.
 2. The apparatus of claim 1 further comprising: a pulse wideextension circuit configured to extend an active period of the commandsignal.
 3. The apparatus of claim 1 further comprising: a logic gateconfigured to provide an inactivation signal to a bank control circuit.4. The apparatus of claim 3, wherein the sense amplifier control circuitis configured to receive the inactivation signal.
 5. The apparatus ofclaim 4, wherein the logic gate is configured to receive a prechargecommand signal.
 6. The apparatus of claim 5, wherein the logic gate isconfigured to receive a bank select signal responsive to a row bankaddress.
 7. The apparatus of claim 1 further comprising: an overdrivecontrol circuit configured to provide an overdrive signal responsive atleast to the delayed command signal.
 8. The apparatus of claim 7 furthercomprising: an overdrive delay circuit configured to provide a seconddelayed command signal to the overdrive control circuit responsive tothe delayed command signal.
 9. The apparatus of claim 8, wherein theoverdrive control circuit comprises: a first overdrive control circuitunit configured to provide the overdrive signal responsive at least tothe second delayed command signal; and a second overdrive controlcircuit unit configured to provide a non-overdrive signal responsive tothe delayed command signal and the second delayed command signal. 10.The apparatus of claim 1 further comprising: a refresh delay circuitconfigured to provide a third delayed active command to the senseamplifier control circuit responsive to the delayed command signal. 11.An apparatus comprising: a delay circuit configured to provide a delayedcommand signal responsive to a command signal; an overdrive controlcircuit configured to provide an overdrive signal responsive at least tothe delayed command signal, wherein the overdrive control circuitcomprises: a first overdrive control circuit unit configured to providethe overdrive signal responsive at least to a second delayed commandsignal; and a second overdrive control circuit unit configured toprovide a non-overdrive signal responsive to the delayed command signaland the second delayed command signal; and an overdrive delay circuitconfigured to provide the second delayed command signal to the overdrivecontrol circuit responsive to the delayed command signal.
 12. Theapparatus of claim 10 further comprising: a register configured toprovide a piece of address information to a sense amplifier controlcircuit responsive to the command signal and the delayed command signal.13. The apparatus of claim 10 thither comprising: a pulse wide extensioncircuit configured to extend an active period of the command signal. 14.The apparatus of claim 13 further comprising a logic gate configured toreceive a precharge command signal.
 15. The apparatus of claim 14,wherein the logic gate is configured to receive a bank select signalresponsive to a row bank address.
 16. The apparatus of claim 10 furthercomprising: a refresh delay circuit configured to provide a thirddelayed active command to a bank control circuit and a sense amplifiercontrol circuit responsive to the delayed command signal.
 17. Anapparatus comprising: a sense amplifier control circuit configured toprovide a first sense amplifier activation signal and a second senseamplifier activation signal responsive at least to a delayed commandsignal, wherein the first and second sense amplifier activation signalseach respectively activates a sense amplifier of a corresponding memorybank in a plurality of memory banks; and an overdrive control circuitconfigured to provide a first sense amplifier overdrive control signaland a second sense amplifier overdrive control signal responsive atleast to the delayed command signal, wherein the first and second senseamplifier overdrive control signals control operations of the senseamplifier of the corresponding memory bank in the plurality of memorybanks.
 18. The apparatus of claim 17, wherein the overdrive controlcircuit comprises: a first overdrive control circuit unit configured toactivate the first sense amplifier overdrive control signal based on thedelayed command signal responsive to an assertion of an sense amplifierbank select signal, wherein the assertion of the sense amplifier banksignal indicates designation of the corresponding memory bank in theplurality of memory banks.
 19. The apparatus of claim 18, wherein theoverdrive control circuit further comprises: a second overdrive controlcircuit unit configured to activate the second sense amplifier overdrivecontrol signal based on a second delayed command signal responsive to anassertion of an overdrive bank select signal, wherein the assertion ofthe overdrive bank select signal indicates designation of thecorresponding memory bank in the plurality of memory banks.
 20. Theapparatus of claim 17 further comprising an override voltage circuitcoupled to the first sense amplifier override control signal and thesecond sense amplifier override control signal, and also coupled to thesense amplifier of the corresponding memory bank of the plurality ofmemory banks to provide a voltage to the sense amplifier responsive toat least one of the first sense amplifier override control signal andthe second sense amplifier override control signal.